The present invention relates to archery sights, and in particular, to archery sights including sight pins that are adjustable to accommodate different shooting distances.
Most conventional archery bows are outfitted with sights that are designed to align the trajectory of an arrow shot from the bow with a target or game. These bow sights include sight pins terminating at a sight indicia—usually a fiber optic point—which must be aligned with the target for accurate shooting,
Often, archers or bow hunters desire to shoot targets or game located at different distances. Accordingly, most bow sights include multiple sight pins having sight indicia aligned along a single, vertical axis or line, one over the other. Each sight indicia is calibrated for a target at a different range. Depending on the target range, the archer must select the corresponding sight pin and align its sight indicia with the target. If the archer's range estimation, pin selection and indicia alignment are correct when the archer shoots the arrow, the arrow will hit the target.
To provide a desired accuracy, a bow sight must be properly tuned. To tune a bow sight each sight pin and corresponding sight indicia must be precisely calibrated for its assigned shooting distance. In doing so, the sight indicia are usually spaced one above the other along the aforementioned common, vertical axis. The spacing between the indicia along the axis depends on the trajectory of arrows shot from the bow. For example, with greater arrow velocity, the indicia can be spaced closer to one another along the vertical axis. Further, as the target range increases, each successive sight indicia must be set at increasing, non-linear intervals along the axis to compensate for the drop of the arrow at those extended ranges.
Bow sight manufacturers usually incorporate adjustment mechanisms to move sight pins to properly tune their bow sights. A popular adjustment mechanism includes a sight pin, which defines a threaded hole, that is slidably positioned in a straight, linear slot defined by the bow sight. A threaded fastener, with a head slightly larger than the slot, is screwed into the hole to clamp the slot between the fastener head and the pin to fix the sight pin and position the sight indicia at a desired position along the vertical axis.
Although this mechanism provides a way to adjust the sight indicia along the vertical axis, it suffers several shortcomings. First, a user must perform several tedious adjustments to move the sight pin. For example, the user must unscrew the fastener, grasp the pin, move the pin, then screw the fastener into the pin to fixedly position the pin. Second, the sight pins on conventional bow sights are miniscule. Therefore, it is usually difficult for individuals with large fingers or arthritic conditions to grasp and precisely move the sight pins. Third, the precision of linear movement of the sight pins within the slot is highly dependent on the steadiness of the user's hand. If the user's hand is unsteady, it can take multiple attempts to precisely position a single sight pin. Accordingly, these conventional sight pin adjustment mechanisms typically fail to provide proper positioning of the sight indicia with rapidity and a high degree of confidence.
In an effort to overcome the above tuning difficulties of popular bow sights, some manufacturers have developed alternative adjustment mechanisms. An example of such a mechanism is disclosed in U.S. Pat. No. 6,634,110 to Johnson. The Johnson mechanism includes a sight pin including a first end that rotates about a single, fixed point. Another end, at which a sight indicia is located, is movable only linearly toward and away from the fixed point. To adjust the Johnson sight pin for a specific range, an archer must rotate the sight pin about the fixed point. Because the sight indicia moves in an arc around the fixed point, the user must then perform a second adjustment to slide the indicia into alignment with the vertical axis of the bow sight.
Although the Johnson mechanism provides a new way to adjust sight pins, it adds additional, complicated mechanisms that must be carefully manipulated to tune the bow sight. Moreover, an archer must exert extra care, and have a well-trained eye, to ensure the added linear adjustment of the sight indicia properly aligns that indicia with the vertical axis.